Sources:
Executive Office of the President of the United States, Office of Management and Budget (OMB), "Budget of the United States Government:
Appendix," Washington, D.C., annual issues, available at
http://www.gpoaccess.gov/usbudget/browse.html as of February 2012.

Executive Office of the President
of the United States, Office of Management and Budget, "Budget of the
United States Government: Analytical Perspective, Detailed Functional
Tables, Washington, D.C., Annual issues, available at http://www.gpoaccess.gov/usbudget/browse.html as of February 2012.